Application Load Balancer (ALB) and Network Load Balancer (NLB) Configuration

This document provides a comprehensive overview of the public-facing Application Load Balancer (ALB) configuration. It covers the listeners that accept incoming traffic, the rules that route requests based on specific conditions, and the target groups that are the final destination for that traffic.

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1. ALB Listeners

Listeners are responsible for checking for connection requests to the ALB, based on the configured port and protocol.

Primary Listener: HTTPS Port 443

This is the main listener that handles the majority of secure web traffic. It uses a set of rules based on the Host Header (domain name) and URL Path to route requests to various target groups. The rules are processed in order of priority (lower numbers have higher priority).

Other Listeners

In addition to port 443, the ALB listens on several other ports with predefined behaviors.

HTTP Port 80

• Action: All traffic arriving on port 80 (HTTP) is permanently redirected (HTTP 301) to https://<host>:443. This enforces that all connections are encrypted over HTTPS.

Other Dedicated HTTPS Ports

These listeners serve specialized backend services and all share a common security policy and SSL certificate.

• Common Security Policy: ELBSecurityPolicy-TLS13-1-2-2021-06
• Default SSL/TLS Certificate: *.solara.io (issued by AWS ACM)

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2. Target Groups

Target Groups (TGs) are used to route requests to one or more registered destinations, such as EC2 instances. All TGs in this configuration share a common base setup.

Common Configuration for All Target Groups

• Target type: Instance
• IP address type: IPv4
• Health check path: /
• Healthy threshold: 5 consecutive successes
• Unhealthy threshold: 2 consecutive failures
• Success codes: 200-499

Important Note: All target groups have two registered instances: onserver-1 and onserver-2.

Detailed Target Group Configurations

The table below lists the specific port and protocol configurations for each individual Target Group.